Configurations of combined series and shunt active filters, also known as Unified Power Quality Conditioners (UPQCs), are designed for simultaneous compensation of voltage and current harmonics and imbalances. Sometimes, compensation of voltage sag/swell is also included as additional functionality of the UPQC. Traditionally, the shunt active filter of the… (More)

The instantaneous active and reactive power theory or the p-q Theory is widely used to design controllers for active filters. This paper deals with some problems due to the misinterpretations of this theory. A historical background of the theory is presented and the problem caused by distorted voltages at the point of common connection (PCC) is analyzed. In… (More)

Certainly, power-electronics devices have brought about great technological improvements. However, the increasing number of power-electronics-driven loads used generally in the industry has brought about uncommon power quality problems. In contrast, power-electronics-driven loads generally require ideal sinusoidal supply voltage in order to function… (More)

Problems related to power quality, which in the last years were responsible only for small losses in low-voltage distribution systems, are now causing damage to power apparatuses and financial losses also in medium-voltage systems. The necessity of a better quality of power supply encourages the development of new specific custom power devices directly… (More)

In the study of the dynamical behavior of doubly-fed induction generators (DFIG), for wind power applications, the use of reduced order models is useful in order to design specific control strategies for wind power plants as well as to obtain lightweight computing simulations. Within this field this paper presents a new dynamic model for wind turbines,… (More)

This paper presents a novel three-phase four-wire low power rating flexible hybrid active filter with a power factor, harmonic and neutral currents capability for distribution systems. The passive filter is tuned to compensate the two largest harmonics components and the power factor of the load. A selective algorithm is employed in order to enable the… (More)

and especially to my fiancée Isabella, I also wish to express my sincere thanks for giving me help, incentive and affection during my stay in Germany. ABSTRACT The use of soft-switching converters in association with switched reluctance motors (SRM) potentially allows the fabrication of motor drives with increased power density and with better efficiency… (More)

This paper presents a frequency switching analysis of an interchanging topology of the Unified Power Quality Conditioner (iUPQC). It includes simulations with hardware-in-the-loop development tool, which allows the control code development (embedded in an actual fixed-point DSP) directly working in a simulated iUPQC (PSCAD/EMTDC simulator). The aim is to… (More)